Dev1: "what was that requirement? I mean, do you remember that little yet hugely important detail ...?"
Dev2: "hmmm sort of ... Maybe it's in one of the emails, possibly 2 months ago. Let's try to find it"
Dev3: "wait, probably Dev1 was not included for some reason in that thread of emails"
Dev2: "no wait, I mean the other, the one we used to talk about those other specifications from previous meeting..."
[and the story goes on]
Now you may think "ok, this event happened once and was a misstep. Shit happens"
Actually, this is the bread and butter in this company I collaborate with. All their requirements are spread across thousands of emails, usually mixed together and possibly forked into different threads. Often people are cut out from conversation because someone forgets to "reply all", other times they're lost in time.
When I asked them "why don't you use some other tool, maybe something more organized and easily searchable, something structured..."
They replied "no no, we prefer to use email for historical reasons"
My brain just melted like chocolate under the sun